1. Field of the Invention
The present invention relates to a printing system and a print control method.
2. Description of the Related Art
In a conventionally proposed printing system, a client apparatus directly outputs a print job to a printer (i.e., an image output apparatus) connected to a local area network. In the above-described conventional printing system, the client apparatus outputs the print job to the printer via a printer driver installed on the client apparatus.
In another conventionally proposed printing system, a client apparatus instructs an image output apparatus to perform print processing via a print service server apparatus connected to the Internet. In the above-described conventional printing system, the print service server apparatus can provide a print-related function. More specifically, the print service server apparatus receives a print job transmitted from the client apparatus and performs bookbinding imposition printing or copy-forgery-inhibited pattern printing, or provides a personal box function, according to the received print job.
According to the above-described conventional printing system in which the client apparatus directly outputs a print job to the printer, a specific function may not be realized if the printer driver installed on the client apparatus is insufficient in capability. For example, when a printer driver of an operating system has the capability of performing bookbinding printing, a printer driver of another operating system may not be able to perform the bookbinding printing.
Further, the realization of a specific function is dependent on the capability of each printer. For example, a printer may not be able to perform the copy-forgery-inhibited pattern printing or may not be able to provide the personal box function.
In this case, if the print service server apparatus in the printing system can provide a function that cannot be provided by the printer driver/printer, the user can use the same printing function constantly regardless of differences in ability or function of the printer driver/printer.
According to the above-described printing system, for example, the printer is connected to the print service server apparatus via a gateway apparatus. In this case, the print service server apparatus cannot directly transmit a print job to the printer. Accordingly, for example, the printer checks about, by polling, the presence of a print job addressed to the apparatus itself that is existing in the print service server apparatus and acquires the job addressed to the apparatus itself.
As discussed in Japanese Patent Application Laid-Open No. 2006-347110, it is conventionally known that an image output apparatus can deliver a multicast message including print attribute information via a network, if the image output apparatus is not ready to print, and can request another image output apparatus in a ready-to-print state to perform proxy printing.
If the polling interval of the printer is set to a significantly long time to eliminate network traffic congestion, the printer may not be able to output a print product promptly in response to a print instruction input by a user via the client apparatus. Hence, it is desired that the printing system can reduce the time lag between the print instruction by the user and the output of the print product, in the following manner.
First, after the client apparatus included in the printing system transmits a print job to the print service server apparatus, the client apparatus delivers a multicast message informing that the printer driver included in the client apparatus has transmitted the print job via a local area network. The printer can detect the transmitted print job upon receiving the multicast message, and can acquire the print job from the print service server apparatus. Thus, it becomes feasible to reduce the time lag between the print instruction by the user and the output of the print product.
However, even in a case where the printer driver notifies the printer of the timing of print job acquisition through multicast, the printer may not be able to perform printing for some reason. For example, the printer cannot perform printing due to lack of paper or lack of toner, or cannot perform printing when the printer performs calibration to adjust the image quality. Moreover, the printer cannot perform printing if the printer is in a power-OFF state, for example, when a failure occurs. In such cases, if a user inputs a print instruction while designating the printer, the user will not notice the above-described unprintable situation until the user comes to the printer setup place to pick up a printed product.
Further, according to the technique discussed in Japanese Patent Application Laid-Open No. 2006-347110, the following problem may arise when the multicast message including the print information is delivered in a case where the output destination printer is not ready to print and the proxy printing is performed by another printer that is ready to print. First, according to the technique discussed in Japanese Patent Application Laid-Open No. 2006-347110, the user is not noticed about the printer that outputs a printed product. Therefore, if the output destination printer did not perform printing, the user is required to check if there is any other printer that has output the print product.
Further, in general, in a case where a printing system performs printing via a print service server apparatus, it is necessary to register an output destination printer (i.e., an image output apparatus) with the print service server apparatus beforehand. Therefore, even when the image output apparatus delivers a multicast message including print information and requests another image output apparatus that is ready to print (i.e., a proxy apparatus) to perform proxy printing, the proxy apparatus cannot perform printing if the proxy apparatus is not registered with the print service server apparatus.